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以工业级硫酸氧钛为原料,以粉煤灰为载体,采用水解法制备了Fe-TiO2/粉煤灰催化剂,通过XRD、SEM、固体紫外-可见光谱对该催化剂进行了表征。以甲基橙作为研究对象,用该光催化剂对甲基橙水溶液进行了光催化降解,比较了不同催化剂、不同Fe3+掺杂量、煅烧温度、催化剂重复使用次数等因素对甲基橙水溶液降解率的影响。结果表明:煅烧温度对催化剂的晶型有一定影响,500℃煅烧条件下TiO2平均晶粒尺寸为28.25nm,锐钛相占约97.4%(wt,质量分数,下同)。Fe3+使得紫外-可见光谱吸收边红移,能吸收可见光,且掺杂0.3%最好。白炽灯下照射3h,0.3%Fe-TiO2/粉煤灰催化剂使甲基橙水溶液降低率达50.6%,相比于TiO2/粉煤灰显示出更高的光催化降解效果。催化剂经活化处理后,相同条件下重复使用5次仍然有较高的催化活性。
The catalyst was characterized by XRD, SEM and solid-state ultraviolet-visible spectroscopy using industrial grade titanyl sulfate as raw material and fly ash as carrier. The Fe-TiO2 / fly ash catalyst was prepared by hydrolysis. Methyl orange as the research object, the photocatalyst photocatalytic degradation of methyl orange aqueous solution was compared with different catalysts, different Fe3 + doping amount, calcination temperature, the number of catalyst reuse and other factors on the methyl orange aqueous solution degradation rate Impact. The results show that the calcination temperature has an influence on the crystal form of the catalyst. The average grain size of TiO2 under calcination at 500 ℃ is 28.25nm, and the anatase phase accounts for about 97.4% (wt, mass fraction). Fe3 + makes the UV - visible spectrum absorption edge redshift, can absorb visible light, and doping 0.3% is best. Under incandescent lamp irradiation for 3h, 0.3% Fe-TiO2 / fly ash catalyst reduced methyl orange aqueous solution to 50.6%, showing higher photocatalytic degradation than TiO2 / fly ash. After the catalyst was activated, the same conditions, repeated use of 5 times still have a higher catalytic activity.